An RPG shot from the motorway? Something along that nature. Close to freezing temps and you would be hard pressed to ignite gasoline let alone get it to explode. Explosions require massive vapors and cold temps keep that in check. Kerosene is very explosive when heated but I have heard of no reports of fire before the explosion.
there is alive report now on bbc, guy in the building was smelling gasoline odor before detonation,
he was at the bbuilding
house collapsed around him, he walked/jumped from 2nd story building down, on debris
he said the building was gone... amazing, guy had scratches...
bbc has live reports ...